I found this old thread doing a google for "true amber", I am in the process of writing a book that explains what it is and how to get it and since others may be looking for it I thought I would add a few things here.
First of all it is a rare genetic trait found in high potency Sativa plants, not Indica, but can be brought out in hybrids. I have linked my site that explains it in my profile under contact info.
I have bred several strains that do it and I have brought it out in both Pineapple Express and Durban Poison.
You need 4 things to see it ,,,,,
A strain that carries the genetic trait
lower light timing, I use 11:20/12:40 (instead of 12/12) as it more resembles what happen in the tropics where these plants flourished.
UVB light
and Sulfur !!!
I use nutes that have sulfur
Gypsum (calcium sulfate)
Epsom (magnesium sulfate)
(I use these instead of a Cal/Mag supplement)
Jack's Citrus FeED 20-10-20 4.9% sulfur
Jack's Aquagold Finisher 7-15-30 9% sulfur
I also use potassium sulfate in the last few weeks of flower
NOTE: there are no toxicity issues with sulfates.
I flower & veg with T5's so for UVB I use ATI True Actinic bulbs, I have 3 of em in a 1000 watt 16 bulb setup I call the Tanning Booth.
The pics are of my strain Colorado Thunderfuck, pic 1 is 5 weeks in flower and pic 2 is 8 weeks in flower it is a 9~10 week strain that is a Sat dom hybrid.
and I'm happy to answer questions
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